Field of the Disclosure
Embodiments of the present disclosure generally relate to apparatus for heating substrates, such as semiconductor substrates.
Description of the Related Art
Semiconductor substrates are processed for a wide variety of applications, including the fabrication of integrated devices and microdevices. One method of processing substrates includes depositing a material, for example, an epitaxial material, on a substrate surface. Deposited film quality is dependent upon several factors, including process conditions such as temperature. As transistor size decreases, temperature control becomes more important in forming high quality films. Additionally or alternatively, deposited materials may be thermally treated, for example annealed, after deposition on a substrate. Consistent temperature control during deposition or thermal treatment results in process-to-process repeatability.
However, each processing chamber utilized to process substrates has slight variations from other chambers, particularly due to machining tolerances of the individual components of each chamber. Thus, each individual chamber has different characteristics during a thermal process, for example, different cooling rates or chamber hot spots, resulting in substrates processed in different chambers having different properties (e.g., chamber-to-chamber variation). The variation between substrates processed on different chambers is amplified as transistor device decreases. Thus, substrates processed on a first chamber will have different properties than substrates processed on other chambers, even though the same processing recipe was used on all the chambers.
Therefore, there is a need for an apparatus that reduces chamber-to-chamber variation of processed substrates.